According to the NCI, each year 5-7 million cancer patients/survivors in the US experience cancer-related psychosocial problems. Results from a survey of over 4,800 cancer outpatients revealed that insomnia, anxiety, fatigue, and depression are four of the most common forms of psychosocial problems reported. For many cancer patients and survivors these problems go unrecognized and undiagnosed, do not dissipate with the completion of medical treatment, and can lead to cognitive difficulties, non-adherence to medical treatment regimen, and reduced quality of life. Recent guidelines outlined by the Institute of Medicine (IOM) (2008), and standard of care requirements by the American College of Surgeons Commission on Cancer (CoC) (2012) and the American Society of Clinical Oncology (ASCO) (2014), require screening all cancer patients/survivors across the U.S. for adjustment problems and referring them for psychosocial services to be treated, beginning in 2015. Fortunately, there are effective Evidence-Based Cognitive and Behavioral Interventions (EBCBIs) to treat cancer-related psychosocial difficulties. A large cadre of supportive care clinicians skilled in EBCBIs is needed to meet the newly identified individuals with psychosocial difficulties once the new guidelines are implemented across the nation. Unfortunately, less than 15% of cancer supportive care clinicians currently report expertise in EBCBI. The proposed R-25E seeks to address that need by training two groups: 1) 320 supportive care clinicians (New Trainees (NTs)) in EBCBIs and 2) 56 clinicians (with prior foundational EBCBI knowledge) to develop into mentors and supervise NTs in how to implement such interventions (Peer Mentor Trainees (PMTs)). The goal of the PMT track is to broaden the reach of our training program by teaching PMTs how to mentor and support the newly trained NTs in EBCBI. Each cycle of 40 NTs receives 6 months of training through 8 pre-workshop didactic webinars, a 3-day experiential skills-based workshop followed by 2 webinars and 6 monthly clinical consultation conference calls with faculty to reinforce learning. Each PMT cycle will span 12 months and will begin with the same basic training provided for NTs for the first 6 months, followed by 6 months of specialized training in peer mentoring and clinical consultation. Specialized PMT training will include: a mentoring/supervision webinar, an onsite mentoring/supervision seminar, attendance at a second NT workshop and 6 monthly clinical consultation calls, during which PMTs will transition into supervisory roles and will receive in-vivo feedback from faculty. Both training tracks (NT and PMT) will be evaluated in terms of: knowledge gained (measured pre/post- training), skill mastery at the completion of training (measured separately for each track), and fidelity of EBCBI implementation (for NTs) and mentoring skills (for PMTs) at home institution 12 months after completion of training. The overarching goal of the proposed R-25E is to train cancer supportive care clinicians to implement EBCBI in order to reduce cancer-related problems and to maximize the impact of the proposed training program.